Sacral ratio and fecal continence in children with anorectal malformations.

Abstract

To evaluate the sacral ratio (SR) in patients with an anorectal malformation (ARM) and verify whether it has predictive value for fecal continence. From January 1990 to April 2002, 42 patients (aged 3-14 years) with an ARM and having already been operated on were reassessed and enrolled in the study. Patients with solid or paste-like stools but no soiling were deemed continent, those with similar stool and episodes of soiling partially continent, and those with no sphincter control, incontinent. The fecal continence was always analysed by the same observer. Sacral radiographic images were reviewed and the SR calculated from anteroposterior and images in the lateral position. All images were obtained before surgery and analysed by the same observer, while a third analysed the results. Results were considered statistically significant at P < 0.001. Seventeen patients were deemed continent, seven partially continent and 18 incontinent; there was no significant difference in SR among the three groups. When fecal continence was analysed in relation to changes in the findings on computed tomography of the lumbosacral spine, patients with sacral agenesis had a significantly higher frequency of fecal incontinence than the others, and all had a SR below 'normal'. Although the SR was different in patients with sacral agenesis it was no different in continent, partially continent or incontinent patients, and thus it is of no practical value in identifying patients likely to have fecal incontinence.